The preparation of cosmetic or pharmaceutical compositions, for example creams, lotions or ointments, requires oil-soluble bases into which in many different lipid-soluble solids are present in dissolved form. A large number of natural and synthetic oils are suitable for this purpose, for example almond and avocado oil or ester oils based on short-chain triglycerides. The oil components in the compositions discussed also have a care action at the same time which is directly connected with skin fatting. Consumers want products which give a nonsticky, very rapidly occurring and longer-lasting feel of skin smoothness and suppleness and moreover are rich and exhibit good skin compatibilities.
The subjective sensation on the skin can be correlated and objectified using the physicochemical parameter of spreading of the oil bodies on the skin, as has been presented by U. Zeidler in Fette, Seifen, Anstrichmitt. 87, 403 (1985). According to this, cosmetic oil bodies can be divided into low-spreading (below 300 mm2/10 min), medium spreading (about 300 to 1000 mm2/10 min) and high-spreading oils (above 1000 mm2/10 min). If a high-spreading oil is used as oil body in a pregiven formulation, then the desired feeling of skin smoothness is very rapidly achieved, although the result does not last for long. Conversely, if low-spreading oils are used, only a less marked feel of smoothness is achieved which remains virtually unchanged over a prolonged period and is therefore likewise unsatisfactory. The obvious combination of a low-spreading and a high-spreading oil surprisingly does not lead to the desired additive effect; instead, the strong smoothing action of the rapidly spreading oil component is perceived subjectively at the start, and then, quite independently, the effect of the slowly spreading oil. In practice, therefore, it is usually necessary to use complex mixtures of oil bodies matched exactly to one another which develop their action successively in the sense of a cascade without having a mutually negative influence. It is clear that the development of such systems is associated with high technical cost and is thus in need of improvement from an economical viewpoint as well.
Consequently, the object of the present invention was to provide novel compositions which have a nonsticky, very rapidly occurring and longer-lasting feel of skin smoothness and suppleness, are rich and have good skin compatibilities. Moreover, they should exhibit a good solution behavior for lipophilic solids.